The present invention relates to apparatus for conveying items from an upstream end to a downstream end of a conveyor system. More particularly, the present invention relates to an indexing and lifting apparatus which accepts randomly spaced items from the upstream end of a conveyor system, indexes the items for processing, and lifts and transfers such items from a first conveyor in a first plane to a second conveyor in a second plane.
Generally speaking, items traveling along a conveyor system are positioned on the conveyor system with random spacing between the items. In some situations it is desirable that the randomly spaced items be indexed so that each item is separately delivered a desired distance apart or at a desired time in order to be processed downstream in the conveyor system. A conveyor system may include a first conveyor and a second conveyor which move items in planes that are at different levels. Thus it may be desirable to index items and to transfer them from the first conveyor in a first plane to a second conveyor in a second plane. In order to transfer items between the different conveyors in a system, items moving along the first conveyor may need to be "primed," i.e., indexed before being fed onto the second conveyor.
While apparatus currently exists for indexing randomly spaced items on a conveyor system so that they are timely delivered at desired spacing therebetween, no apparatus currently exists for both indexing and lifting randomly spaced items from a first conveyor in a first plane to a second conveyor in a second plane. Therefore, a need exists for an apparatus combining both indexing and lifting functions.
According to the present invention, an apparatus for indexing and lifting randomly spaced items from a first conveyor in a first plane and transferring such items to a second conveyor in a second plane at a different level than the first plane is provided. The apparatus includes a transfer assembly and members for mounting the transfer assembly at an angle relative to one of the first and second planes of the first and second conveyors so that items are transferred from one plane to the other. The apparatus further includes posts that are connected to the transfer assembly for supporting and carrying the items. The posts are connected to the transfer assembly and are configured so the top surfaces of the posts are in a single plane which is parallel to at least one of the first and second planes of the first and second conveyors. One of the posts is a leading post and the other post is a trailing post. The trailing post includes a stop for engaging an item received from the first conveyor in order to index items as they are transferred from the first conveyor and to lift such items to the second conveyor.
Further in accordance with the present invention, an apparatus for indexing and lifting randomly spaced items from a first conveyor in a first plane to a second conveyor in a second plane includes both an indexing assembly for indexing items while they are moving on the first conveyor and a lifting assembly for lifting the indexed items from the first conveyor to a second conveyor in a plane different than the plane of the first conveyor. The indexing assembly serves to "prime" the items while on the first conveyor before they are fed onto the lifting assembly. The indexing assembly comprises a transfer assembly, a plurality of lugs, and pivot connectors for pivotally connecting the lugs to the transfer assembly. The lugs are connected to the transfer assembly in a spaced relationship that is less than a longitudinal dimension of the items that are being transferred on the conveyors. The indexing assembly further includes members for mounting the transfer assembly adjacent to the first conveyor and a drive mechanism for driving the transfer assembly to move the lugs at a speed less than the speed of the first conveyor. Each of the lugs has an engaging member and a weighted portion for pivoting the lugs as they travel on the transfer assembly so that the engaging member can engage a leading edge of an item while it is moving on the first conveyor to catch the item and separately deliver that item to the lifting assembly.
Advantageously, the indexing and lifting apparatus of the present invention is particularly well suited to high speed operation of first and second conveyors. Further, the indexing and lifting apparatus is particularly suited for items with sides that are perpendicular to their bottoms, thus providing a leading edge for engaging the indexing lugs and the stops in the trailing posts of the lifting assembly.
One of the features of the present invention is that the indexing assembly serves to prime the lifter assembly between gaps in the flow of items along the first conveyor. However, it is also a feature of the present invention that the lifting assembly can be used by itself without the indexing assembly to index and lift items. In this later mode of operation, the lifting assembly can be primed by the use of a control system and electric eyes to ensure a constant flow of items onto the lift assembly.
Additional objects, features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.